Drive smart

Transportation accounts for nearly 30% of Boston’s greenhouse gas emissions. Through a few easy tips, you can do your part to stop releasing emissions.

Don’t drive if you don’t have to

Walk, bike, carpool, and ride the T: You can give it a try by hosting a car-free Friday at your workplace. The State of Massachusetts also hosts a Car-Free Week in 2013.

Drive more efficiently

Do not idle: It’s the law, and it saves gas. Restarting the engine uses about the same amount of gas as idling for 30 seconds.

Stick to the speed limit: Driving 55 instead of 50 raises your gas mileage by about 5 percent. Also avoid very rapid acceleration, which will waste gas.

Try a driving app: The U.S. Department of Energy held a challenge for developers to create apps that would lead to more efficient driving. One winner, Fuel Economy Coach, uses your smartphone to measure how you’re driving and gives you tips to increase fuel economy.

Keep your car in shape

Check your air filter: Replacing a clogged air filter can improve your car’s gas mileage by as much as 10 percent.